SQLite

** Code for testing the virtual table interfaces.  This code
** is not included in the SQLite library.  It is used for automated
** testing of the SQLite library.
**
** The emphasis of this file is a virtual table that provides
** access to TCL variables.
**
** $Id: test_tclvar.c,v 1.14 2007/08/21 10:44:16 drh Exp $
** $Id: test_tclvar.c,v 1.15 2008/05/29 05:23:42 drh Exp $
*/
#include "sqliteInt.h"
#include "tcl.h"
#include <stdlib.h>
#include <string.h>

#ifndef SQLITE_OMIT_VIRTUALTABLE

}

static int tclvarBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
  int ii;

  for(ii=0; ii<pIdxInfo->nConstraint; ii++){
    struct sqlite3_index_constraint const *pCons = &pIdxInfo->aConstraint[ii];
    if( pCons->iColumn==0 && pCons->op==SQLITE_INDEX_CONSTRAINT_EQ ){
    if( pCons->iColumn==0 && pCons->usable
           && pCons->op==SQLITE_INDEX_CONSTRAINT_EQ ){
      struct sqlite3_index_constraint_usage *pUsage;
      pUsage = &pIdxInfo->aConstraintUsage[ii];
      pUsage->omit = 0;
      pUsage->argvIndex = 1;
      return SQLITE_OK;
    }
  }

  for(ii=0; ii<pIdxInfo->nConstraint; ii++){
    struct sqlite3_index_constraint const *pCons = &pIdxInfo->aConstraint[ii];
    if( pCons->iColumn==0 && pCons->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
    if( pCons->iColumn==0 && pCons->usable
           && pCons->op==SQLITE_INDEX_CONSTRAINT_MATCH ){
      struct sqlite3_index_constraint_usage *pUsage;
      pUsage = &pIdxInfo->aConstraintUsage[ii];
      pUsage->omit = 1;
      pUsage->argvIndex = 1;
      return SQLITE_OK;
    }
  }

**
** Various scripts scan this source file in order to generate HTML
** documentation, headers files, or other derived files.  The formatting
** of the code in this file is, therefore, important.  See other comments
** in this file for details.  If in doubt, do not deviate from existing
** commenting and indentation practices when changing or adding code.
**
** $Id: vdbe.c,v 1.742 2008/05/29 03:12:55 drh Exp $
** $Id: vdbe.c,v 1.743 2008/05/29 05:23:42 drh Exp $
*/
#include "sqliteInt.h"
#include <ctype.h>
#include "vdbeInt.h"

/*
** The following global variable is incremented every time a cursor

** P4 is either NULL or a string that was generated by the xBestIndex
** method of the module.  The interpretation of the P4 string is left
** to the module implementation.
**
** This opcode invokes the xFilter method on the virtual table specified
** by P1.  The integer query plan parameter to xFilter is stored in register
** P3. Register P3+1 stores the argc parameter to be passed to the
** xFilter method. Registers P3+2..P3+1+argc are the argc additional
** parametersneath additional parameters which are passed to
** xFilter method. Registers P3+2..P3+1+argc are the argc
** additional parameters which are passed to
** xFilter as argv. Register P3+2 becomes argv[0] when passed to xFilter.
**
** A jump is made to P2 if the result set after filtering would be empty.
*/
case OP_VFilter: {   /* jump */
  int nArg;
  int iQuery;

** This module contains C code that generates VDBE code used to process
** the WHERE clause of SQL statements.  This module is reponsible for
** generating the code that loops through a table looking for applicable
** rows.  Indices are selected and used to speed the search when doing
** so is applicable.  Because this module is responsible for selecting
** indices, you might also think of this module as the "query optimizer".
**
** $Id: where.c,v 1.305 2008/05/28 18:01:45 shane Exp $
** $Id: where.c,v 1.306 2008/05/29 05:23:42 drh Exp $
*/
#include "sqliteInt.h"

/*
** The number of bits in a Bitmask.  "BMS" means "BitMask Size".
*/
#define BMS  (sizeof(Bitmask)*8)

      iReg = sqlite3GetTempRange(pParse, nConstraint+2);
      pParse->disableColCache++;
      for(j=1; j<=nConstraint; j++){
        int k;
        for(k=0; k<nConstraint; k++){
          if( aUsage[k].argvIndex==j ){
            int iTerm = aConstraint[k].iTermOffset;
            assert( pParse->disableColCache );
            sqlite3ExprCode(pParse, wc.a[iTerm].pExpr->pRight, iReg+j+1);
            break;
          }
        }
        if( k==nConstraint ) break;
      }
      assert( pParse->disableColCache );
      pParse->disableColCache--;
      sqlite3VdbeAddOp2(v, OP_Integer, pBestIdx->idxNum, iReg);
      sqlite3VdbeAddOp2(v, OP_Integer, j-1, iReg+1);
      sqlite3VdbeAddOp4(v, OP_VFilter, iCur, brk, iReg, pBestIdx->idxStr,
                        pBestIdx->needToFreeIdxStr ? P4_MPRINTF : P4_STATIC);
      sqlite3ReleaseTempRange(pParse, iReg, nConstraint+2);
      pBestIdx->needToFreeIdxStr = 0;
      for(j=0; j<pBestIdx->nConstraint; j++){
      for(j=0; j<nConstraint; j++){
        if( aUsage[j].omit ){
          int iTerm = aConstraint[j].iTermOffset;
          disableTerm(pLevel, &wc.a[iTerm]);
        }
      }
      pLevel->op = OP_VNext;
      pLevel->p1 = iCur;

      start_constraints = pRangeStart || nEq>0;

      /* Seek the index cursor to the start of the range. */
      nConstraint = nEq;
      if( pRangeStart ){
        int dcc = pParse->disableColCache;
        if( pRangeEnd ){
          pParse->disableColCache = 1;
          pParse->disableColCache++;
        }
        sqlite3ExprCode(pParse, pRangeStart->pExpr->pRight, regBase+nEq);
        pParse->disableColCache = dcc;
        sqlite3VdbeAddOp2(v, OP_IsNull, regBase+nEq, nxt);
        nConstraint++;
      }else if( isMinQuery ){
        sqlite3VdbeAddOp2(v, OP_Null, 0, regBase+nEq);